The letters are invisible to the naked eye, and can only be read with a medical microscope at 400 times magnification.

这些字母小到用肉眼无法识别，只能用放大400倍的医学显微镜才能看清。

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The paper tells about Latest scientific research abroad on medical microscope, laparoscope, Joint-scope, narcotic machine, breathing machine and pumping machine, etc.

本文介绍了国外医用手术显微镜、腹腔镜、关节镜、麻醉机、呼吸机、抽吸器等设备的最新科研情况。

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Results of a large number of biological and medical assays interpreted through a microscope.

FORBES: The Socialization of Microscopes

At McAllen Medical Center, I saw an orthopedic surgeon work under an operating microscope to remove a tumor that had wrapped around the spinal cord of a fourteen-year-old.

NEWYORKER: The Cost Conundrum